Patient, parent and professional expert perspectives on personalized regenerative implants: a qualitative focus group study

Background: Perspectives of patients, parents and professional experts on personalized regenerative implants for regenerative medicine purposes are largely unknown. Method: To better understand these perspectives, we conducted four focus groups with professional experts of mixed European nationality (n = 8), Dutch patients with regular implants (n = 8), Dutch and Belgian (n = 5) and Spanish (n = 8) parents of children with cleft palate. Results: Two overarching themes were identified: ‘patient-centered research and care’ and ‘ambivalent attitudes toward personalized regenerative implants’. Discussion: The results reveal that stakeholders should adopt a participatory rather than an impairment discourse and address the ambivalence among professional experts, patients and parents. Conclusion: Considering stakeholder perspectives facilitates ethical and responsible development and use of personalized regenerative implants.


I ntro duction
A shift is taking place in the field of medical implants.For decades, off-the-shelf and inert implants, like metal and plastic implants for knee and hip replacements (her eafter r eferr ed to as r egular implants) w er e primar ily used.R ecen tly, a new genera tion of implan ts has emerged for tissue engineering and r egenerativ e medicine [1][2][3].These implants are regenerative, because they facilitate cell growth by serving as a scaffold (artificial extracellular matrix) for tissue repair and regeneration.Once a physiologically and structurally functional tissue has formed, these implants typically biodegrade, meaning that they break down into nontoxic by-pr oducts and leav e the body after a certain period.These implants can also be personalized to fit the pa tien ts' bodies and are mostly created using additive manufacturing.Personalized r egenerativ e implants ar e currently being developed for healthcare applications including the trea tmen t of musculoskeletal disease.The focus of this paper will be on cleft palate and joint defects.
Curren tly, cleft pala te is trea ted through a series of surger ies perfor med between birth and adulthood (ar ound 18 y ears old), inv olving palatoplasty and r ecurrent insertion of ven tila tion tubes in the ear, followed by subsequent surgeries addressing issues like maxillary closur e, speech pr oblems or aesthetic c onc er ns [ 4 ].Dur ing these surgeries, autogenous bone grafting is commonly used for bone regeneration.Personalized regenerative implants offer a promising alt ernative, g rowing with the child's development and potentially streamlining the proc ess t o a single surgery.Also, they hold the potential to achiev e closur e of both har d and soft palates using a combination of materials.
Curr ent tr eatments for joint def ects in v olv e nonr egenera tive implan ts or autologous, allogenic and xenogenic bone grafting often lacking pa tien t-specific dimensions, r egenerativ e pr operties , stable materials , regular surfaces (compared with native tissue) and mechanical stability [ 5 ].Personalized r egenerativ e implants, like an osteochondral or meniscus implant for the knee joint, present a potential solution, tailoring the implant to the individual, reducing surgery duration, ensuring mechanical stability, fostering tissue r egeneration, pr ev ent shrinkage and allowing the use of multiple materials simultaneously.
To use personalized r egenerativ e implants responsibly in healthcare, the ethical issues that play a role in implant development and use need to be underst ood.Existing lit erature has identified various ethical issues related to inert regular implants and regenerative medicine applications, including tissue engineering and biofabr ication [6][7][8][9][10].R ec ent review s raised awareness of under explor ed ethical issues of tissue engineering for r egenerativ e pur poses, including ir r ev ersibility, the inclusion of gender differences and embodiment, with only one of these reviews focusing on personalized r egenerativ e implants [ 11 , 12 ].Mor eov er, qualitativ e studies have been published in which professional experts share their insights on the ethical aspects of regenerative medicine applications in orthopedics and congenital birth defects in children, all involving the use of stem cells [13][14][15].Important ethical themes in these studies relat ed t o pot ential serious adverse effects, like the increased risk of cancer, the source of cells and the cell donation process [ 14 , 15 ].However, issues related to the use of stem cells such as source of cells and donation pr ocess ar e not r elev an t for cell-free implan ts, which are the central focus of this paper.Additionally, multiple qualitative studies have explored pa tien ts' experiences with regular implants, including total knee replacements and par ents' perspectiv es on cleft palat e servic es [16][17][18][19].The themes that are discussed within these studies ar e r elat ed t o the lived experienc es of implan t recipien ts, such as embodiment, bodily sensations, psychological fact ors and int erpersonal skills of healthcar e pr ofessionals [16][17][18][19].
While there is qualitative literature on how professional experts think about ethical aspects of r egenerativ e medicine applications (including the use of st em c ells) in different fields and how pa tien ts and paren ts of children think about regular trea tmen ts for join t defects and cleft palate, it is largely unknown how these pa tien ts, paren ts and professional experts think about personalized regenera tive implan ts.Learning mor e about their perspectiv es is relev an t because it can assist in aligning the design and implemen ta tion of these implants with the needs and desires of stakeholders such as pa tien ts, engineers and clinicians.
This paper presents the results of a focus group study into the perspectives of pa tien ts, paren ts and professional experts on personalized r egenerativ e implants.These insights are linked to the results of previously published literature.By doing so, this analysis contributes to the r esponsible dev elopmen t and implemen ta tion of newly emerg ing t echnolog ies in r egenerativ e medicine, while also providing practical guidance for the implemen ta tion of these t echnolog ies in r eal-w or ld scenar ios.

M etho ds
In this study, we in vestigated prof essional experts' , pa tien ts' and paren ts' perspectives on personalized r egenerativ e implants through a qualitative focus group study.Focus groups are a qualitative research method to gather a compr ehensiv e understanding of attitudes, opinions and experiences within a specific c ont ext [ 20 ].The interaction among participants is used to obtain broader and deeper information than is possible in an individual interview.This focus group study is part of the INKplant consortium, which seeks to dev elop personalized r egenerativ e implants for tissue engineering and r egenerativ e medicine using differ ent biomaterials, high-r esolution additiv e manufacturing and adv anced simula tion and biological ev alua tion.The study is reported following the c onsolidat ed crit eria for r eporting qualitativ e studies guidelines [ 21 ].

Pa rticipa nt selection & recruitment
The participants of this study w er e divided into three differ ent gr oups of stakeholders ( Table 1 ).The first group [n = 8] w er e pa tien ts in the Netherlands who will get or have already gotten regular inert synthetic shoulder, knee or hip implants.Among this gr oup, tw o pa tien ts underwen t experimen tal trea tmen ts involving the use of biological materials or stem cell therapy, while the remaining six participants r eceiv ed state-ofthe-art implants.The second group (n = 13) were parents whose children had undergone current state -of-the -art trea tmen t options, including var ious surger ies perfor med from birth to adulthood (around 18 years old) to treat cleft palates and maxillary openings.This group was divided into two focus groups: one with parents from the Netherlands and Belgium (n = 5) and the other with Spanish parents (n = 8).The last group (n = 8) w er e orthopedic surgeons, biomedical engineers and r esear chers fr om differ ent Eur opean countries.These pr ofessional experts all worked in the field of r egenerativ e medicine and tissue engineering and had extensive knowledge of personalized r egenerativ e implants.
Dutch pa tien ts w er e r ecruited via R. Custers's network of clinicians in the University Medical Center Utrecht and via Dutch pa tien t organiza tions 'R euma Neder land' and 'Osteopor ose Ver eniging' and their social media channels.Dutch parents of children with cleft palate w er e recruited via Schisis Nederland and their social media channels.Spanish parents of children with cleft palate w er e r ecruit ed via E. Martínez-Sanz t ogether with clinicians fr om tw o hospitals in Madrid (Gr egorio Marañón The r esear ch pr ot oc ol was submitt ed t o the r esear ch ethics c ommitt ee of the University Medical Center Utrecht for review before starting the research.The c ommitt ee det ermined that this study was exempt from the Medical Research Involving Humans Act (r esear ch pr oposal no.21/828).In line with the r esear ch prot oc ol, we obtained writt en informed c onsent from all participants.

Data collection
Focus gr oups w er e c onduct ed betw een Mar ch 2022 and March 2023.The focus g roups last ed between 90 and 120 min.All focus groups took place online via MS Teams due to covid-19 restrictions, climate change considerations and ac c essibility reasons.The focus groups were c onduct ed in Dut ch, English or Spanish.The Spanish focus group was moderated by E. Martínez-Sanz and observed by N. de Graeff.The other focus groups were moderated by M. van Daal and observed by A. de Kanter or N. de Graeff.The topic list of the focus groups was based on a pr evious r eview of the ethical aspects of personalized r egenerativ e implants [ 11 , 12 ] and discussions among the r esear ch team and the INKplant consortium.The int erview s c onsist ed of openended questions related to hopes , expectations , potential benefits and risks and potential ethical implications of the personalized r egenerativ e implants.These questions allowed participants to bring up or emphasize specific issues they consider ed r elev an t, while also ensuring some c onsist ency in the topics that w er e discussed to explore how differen t participan ts viewed these t opics.A s is typical of qualitative research, the topics evolved during the focus groups.The participants were in the lead of the conversation.The focus gr oups w er e r ecor ded , transcr ibed ver ba tim, transla ted in to English (when necessary) and pseudonymized.

Dat a analy sis
Data from this study was analyzed thematically.In general, da ta analysis w as based on the constan t compara tive method , which inv olv es r eviewing the data to dev elop to develop codes, concepts and themes by continually revisiting the data for both supportive and conflicting evidence [ 22 ].M. van Daal and A. de Kanter coded the full transcripts by labeling units of texts that r eferr ed to one or more topics relev an t to the study.Nvivo 12 software was used for c oding.Aft erwar d , M. van Daal and A. de Kant er c ompared and checked the c odes for c onsist ency and critically discussed the in terpreta tions and suitability of the codes.The codes w er e adjusted acr oss transcripts.Aft er c onsensus on c oding was r eached , the codes w er e developed into higher-order c onc epts and themes and discussed among all authors.This process was iterative by r epeatedly r evisiting the data.Repr esentativ e quotes w er e chosen t o illustrat e the patients' , parents' and professional e xperts' e xperienc es and translat ed int o English by M. van Daal.

Results
The analysis of the results of the focus groups have led us to identify two overarching themes: (1) pa tien t-cen tered r esear ch and car e and (2) ambiv alen t a ttitudes tow ard personalized r egenerativ e implants.T hese o v erar ching themes and related subthemes were discussed by partic-ipan ts in differen t w ays, as we will discuss below.Not all subthemes w er e discussed in all focus gr oups.

Theme 1: Patient-centered research & care
The first ov erar ching theme that emerged from the focus groups was the importance of pa tien t-cen ter ed r esear ch and care.Pa tien ts and paren ts of children with cleft palate underlined points of impr ov ement r egar ding the care they had received thus far on the one hand and wishes they had with r egar d to the care surrounding futur e r egenerativ e implants, on the other hand .Pr ofessional experts also identified points for impr ov ement for pa tien t-cen ter ed r esear ch.Thr ee subthemes w er e identified: (a) support and expectation management , (b ) institutional and interdisciplinary collaboration, (c) the implan t's con tribution to living one's life.

Support & expectation management
Pa tien ts with regular implants expressed a need for a better support system during their trea tmen t and recovery journey.Pa tien ts emphasized effective communication and the importance of recognizing the myriad challenges stemming from their comorbidities, as important elements of their support.Some pa tien ts indica ted tha t they did not always experience the acknowledgement of these challenges and that bett er c ommunication would have significantly helped them throughout their trea tmen t journey.How ev er, par ents of childr en with cleft palate praised the extraordinary support they received from their healthcare professionals.Parents even referred to them as their 'cleft palate family' ( Table 2 , quote 1).
Parents and patients emphasized the sig nificanc e of expecta tion managemen t as a crucial element of presurgical support.Various parents explained that they r eceiv ed valuable tips and insights from clinicians and other healthcare professionals, enabling them to be better informed about the upcoming surgery and its challenges.They also highlighted that providing this compr ehensiv e information about what to expect from surgery and the need for clear guidance was important for future trea tmen ts with personalized regenerative implants ( Table 2 , quote 2).Some patients who had alr eady r eceiv ed r egular implants expr essed that the medical team had fallen short in terms of expectation management in the care they had r eceiv ed .Sev eral pa tien ts had been g iven c ertain expecta tions tha t led to disappoin tmen ts during their trea tmen t journey.For instance, one pa tien t highligh ted tha t if they had been better informed and guided in the beginning, they possibly could have avoided some of the surgeries and could have made a more informed choice about whether to undergo another surgery or not ( Table 2 , quote 3).
For many pa tien ts, the trea tmen ts turned out to be more complex than an ticipa ted and the outcomes of these trea tmen ts w er e disappointing, r esulting in mental and emotional impacts.Pa tien ts highligh ted tha t it w as important to them that the medical team draws a realistic pictur e (r egar ding all possible side effects, complications and the rehabilitation process) and offers them emotional guidanc e t o navigat e the emotional challenges of the trea tmen t process.This would enable the pa tien ts to make informed decisions about future trea tmen ts with personalized r egenerativ e implants ( Table 2 , quote 4).
During the professional expert focus group, the inv olv ement of patients and the public in r esear ch was mentioned as a way to manage the expectations of these g roups.For instanc e, professional experts highlighted that engaging with patients and the public through interactiv e w orkshops to explain r esear ch goals, methodologies and setting realistic timeframes helps to bridge the gap between scientific research and the pa tien ts and the public and ensures they are well-informed throughout the process.

Institutional & interdisciplinary collaboration
Pa tien ts and parents emphasized that institutional collaboration sometimes lags behind ( Table 2 , quote 5).For instance, one pa tien t shared a personal experience about their trea tmen t with regular implants which had failed due to the transfer to another hospital , r esulting in missed injuries or lesions and c onsequently, inc orrect trea tmen t.Some pa tien ts r eceiv ed tr ea tmen t from different hospitals for various issues and did not have ac c ess to all their medical information, leading to challenges in receiving optimal care ( Table 2 , quote 6).Therefore, pa tien ts emphasized the sig nificanc e of increased c ollaboration among healthcar e pr ofessionals acr oss differ ent disciplines within hospitals and beyond to improve the quality of (new) trea tmen ts such as regenerative implants.The professional experts also acknowledged that institutional collaboration should be impr ov ed .
Parents of children with cleft palate also reported a lack of such interdisciplinary collaboration between institutes, but generally expr essed positiv e experiences with collaboration among various healthcare professionals in different fields within the same hospital.They valued the consultation meetings held once or twice a y ear, inv olving all stakeholders, including the orthodontist , dentist , psychologist , speech therapist , nutritionist and surgeon.The fact that the healthcare professionals c ommunicat ed ext ensiv ely with each other in fr ont of the paren ts w as helpful ( Table 2 , quote 7).How ev er, parents questioned the variety of approaches taken by hospitals, including v aria tions in the age a t which the first cleft palate surgery is performed and differences Table 2. Illustrative quotes about patien t -cen ter ed r esear ch and car e. Support 1 DP3: Yes, from, or after the palate closure I believe, I don't remember exactly, but since about six years we meet annually or biennially with those inv olv ed in the cleft palat e t eam t o sit at the table with us as par ents and the child .So the next steps ar e indeed taken in a multidisciplinary manner and are also discussed with you present.So yes, it does kind of feel like your "cleft palate family" taking care of your child.I also have a lot of c onfidenc e in it and the c ommunica tion is good.-Dutch parent 2 SP7: No, P5 raises a very interesting subject because in the end we all know it well, cleft palate is not the same, there are as many cases as ther e ar e childr en, right?So in the end , r egar ding the suc c ess ra t e it would be important t o consider it because, we do not kno w, right?No, it is not the same unilateral, bilateral and there are a thousand, a billion cases, so (…) if the professional could guide us on the success rate of doing it in one way or another, I think it would be very important, because from there, as P5 says, you can decide, right?So look, in the traditional method y ou hav e ninety percent and they never tell you because they can't tell you, right?But a very high percentage or 'look it is the best option you have because the case is very c omplica ted and and we think this is the best option for your son' , well, then you can evalua te it .-Spanish parent 3 P2: And yes, when looking at myself, my knee has been open four-times and yes, like [P5] says: at some point you make a decision, like when you can no longer walk or there's pain every day, then it is worth opening it up again.However, it doesn't get any better and you know that as w ell .Aft er the first time, it wasn't t oo bad , but then ev ery next time new issues arise, such as scar tissue and irritation.So the thr eshold is getting higher and higher.And then I think; maybe if I had been guided much better in the preliminary phase by speaking to this group of people, or by being informed much better on the c onsequenc es, then that might have saved me one or two operations.Because then you will really start to think more seriously and perhaps make the better choice at the start of things, or not make it and postpone it for later, in order to make a better choice 3 years later for instance.So I think there is a lot to be gained, especially in the preliminary stages.-Patient 4 P2: We've all been through one or more surgeries and after, you find out that things aren't as promising as you thought they would be, or as it was presented to you.And in my experience, with r egar d to the preparation, in the preliminary phase, I think there should be much more a ttention on wha t awaits you and a mor e r ealistic pictur e should be drawn c onc erning all the side effects and additional ailmen ts, that en tire r ehabilitation pr ocess actually.give permission again to one, because otherwise, they are not allowed to forward it to the other.And then they say: just take it on a disk, because that works even better.I think that's so completely old-fashioned.-Patient 7 DP2: Yeah, gosh, all I can say is that I think it's fantastic, really.Depending on what stage we were a t , we saw only certain doctors, but once a y ear w e also had something called a cleft pala te c onsulta tion.And then the entir e team is pr esent , c omprised of an orthodontist , a dentist , the head of the team, the surgeon who will perform the next operation, a psychologist, a speech therapist, a nutritionist.(…) So yes, that was very nice and convenient as well, because as a parent you don't always… sometimes so much is said, you don't remember everything or you don't fully understand it all.The fact that they communicated a lot among themselves and that they w er e often all present during a c onsulta tion, c ommunica ting with each other, while y ou, as a par ent, w er e pr esent , I found tha t very pleasant . in methods for closing hard and soft palates ( Table 2 , quote 8).They encouraged hospitals to align approaches and work together both nationally and internationally to impr ov e the implemen ta tion of new trea tmen ts such as r egenerativ e implants.
In addition, professional experts acknowledged that they are inclined to solely operate within their specific r esear ch domains ( Table 2 , quote 9) and view the r esear ch pr ocess fr om their own perspectiv es by focusing on finding the best measurement for their r esear ch objectiv es and gather extensiv e data on their r esear ch topic .Pr ofessional experts mentioned thr ee elemen ts tha t could help mitiga t e the t endency t o only operate within specific r esear ch domains and ther eby c ontribut e t o int erdisciplinary c ollaboration and an integ rat ed r esear ch appr oach in the field of r egenerativ e medicine.First, practicing empathy and gaining a deeper understanding of the experiences and needs of these stakeholders can sig nificantly c ontribut e t o the r esear ch out c omes.For instanc e, one professional expert emphasized the importance of stepping into the shoes of the pa tien ts and orthopedic surgeons ( Table 2 , quote 10).Second, they emphasized the importance of adopting a forwar d-thinking appr oach right fr om the start of their r esear ch pr ojects.For instance, one pr ofessional expert men tioned tha t when developing a new ma terial for 3D printing, it is crucial to also consider the clinical aspects to ensure its applicability in r eal-w orld settings.The professional experts proposed a shift toward a more entr epr eneurial mindset, wher e r esear chers hav e a w elldefined product in mind early on and work toward that goal .Thir d , pr of essional experts suggested in vesting in collaborativ e appr oaches, such as multidisciplinary c onsortia, c onducting focus groups together and facilita ting in terdisciplinary meetings.By ga thering input from differ ent pr ofessional experts, r esear chers could gain v aluable insigh ts, especially those who are not part of a multidisciplinary consortium and/or working on more fundamental projects.

Living one's life
Certain pa tien ts expressed tha t healthcar e pr ofessionals focused too much on rectifying a defect (e.g. a damaged shoulder) and sometimes overlooked their broader wishes and needs.Pa tien ts shared experiences of interacting with their clinicians in which the clinician focused pr imar ily on the (physical and technical) functioning of their implant.For example, when a pa tien t expressed the desir e and per ceiv ed need of being able to sit on her (implant ed) knee, her phy sician questioned the nec essity of being able to do so ( Table 2 , quote 11).She explained her independent living situation, emphasizing her wish to mov e fr eely.This example sheds light on how clinicians may sometimes overlook or fail to fully comprehend the desires and needs expressed by their pa tien ts.To preven t this, pa tien ts emphasize the importance of healthcare professionals listening a tten tively and delving deeper into the personal experience of living with a specific disease or condition.
Furthermore, pa tien ts expressed tha t it w as importan t to them that the implant would enable them to live their lives to the fullest.For instance, pa tien ts raised important questions r egar ding their post-tr ea tmen t abilities, expressing c onc erns r egar ding t o what ext ent they w ould r egain the ability to walk their dog, run or swim after undergoing r egenerativ e implant treatment.The discussions around regenerative implants prominently r ev olv ed ar ound the c onc epts of independenc e and mobility, highlighting the need for freedom of movement and c onc erns about the pot en tial limita tions thereof.The ability to move independently was viewed as beneficial in supporting both physical well-being and personal fulfillmen t.A pa tien t expressed that had they known beforehand about the ext ent t o which their movements would be restricted by the (regular) implant, they might have chosen not to undergo the trea tmen t ( Table 2 , quote 12).
In line with this, parents expressed a desire for their children to experience a more uninterrupted childhood, with decreased emotional and physical suffering experienced by their children as a result of the surgeries and r ehabilitation.Corr espondingly, they consider ed the poten tial tha t regenera tive implan ts migh t offer f or fewer surgeries as beneficial for their children as well as themselves ( Table 2 , quotes 13 and 14).

Theme 2: Ambivalent attitudes toward personalized regenerative implants
A second theme explored in the focus groups concerned participants expressing ambivalent attitudes toward the characteristics of personalized r egenerativ e implants, such as their r egenerativ e capacity, the novelty of this technology and the possibility for personaliza tion.In terestingly, the ambiv alen t rela tionship with regenera tive implan ts w as also reflected in the metaphors and language pa tien ts used to talk about them.Finally, the sig nificanc e of age as an important selection cr iter ion for r egenerativ e implants was a matter of contrasting perspectives and this divergence in views was particularly pr onounced betw een pa tien ts and professional experts.

Regeneration
The r egenerativ e capacity emerged as a topic of interest in all focus groups, with participants expressing both the adv an tages and disadv an tages of regenera tive implan ts.
This ambivalence is reflected in two ways, namely in how they talked about tissue growth and about the fixation of the r egenerativ e implant in the body.Regar ding gr owth, one important benefit, as highlighted by several participants, is the possibility of the implant leading to the tissue growth and replacement of the implant by the body's own tissue.This was per ceiv ed as adv an tageous since the body takes over, which one parent described as a 'natural' good solution for their child ( Table 3 , quote 1).Additionally, some participants expressed c onfidenc e that this r egenerativ e aspect would benefit the r ecov ery and healing process.In contrast to these benefits, parents also expressed c onc erns r egar ding the pr oc ess of tissue g rowth and its poten tial implica tions.They w onder ed whether the implant and tissue would grow adequately with the child's body as he or she ages, ensuring a functional palate in the long run.Furthermor e, ther e w er e appr ehensions about the possibility of uncontrolled tissue growth, such as tumor formation, as a potential risk associated with the r egenerativ e aspect of the implant.Participants sought clarification on whether the tissue growth would stop at a certain point and how it would be controlled ( Table 3 , quote 2).One parent mentioned feeling uneasy about the idea of something growing inside their child's body but also mentioned that they could get used to this idea over time ( Table 3 , quote 3).
Regar ding fixation, pr ofessional experts noted that r egenerativ e implants ar e appealing because of their integra tion in to the body's 'natural' structure and therefore ar e mor e secur ely anchor ed in the body than r egular implants, such as metal implants ( Table 3 , quote 4).In con trast, one pa tien t ar gued in fa vor of an implan t tha t is fixed and not r egenerativ e because it feels stable within their body and less likely to mov e ar ound ( Table 3 , quote 5).The pa tien t cited examples of br east pr ostheses and meshes tha t migra ted through the body and caused health problems to emphasize their pr efer enc e for fixation.In connection to this, another pa tien t expressed c onc erns about the per ceiv ed fragility of r egenerativ e implants and feared that it might be susceptible to breaking.

Novelty
T he no v elty of the r egenerativ e implant technology evokes both excitement and uncertainty among participan ts.Pa tien ts and paren ts expressed en thusiasm for the advanced 3D-printed implant, seeing it as incredible adv ancemen t ( Table 3 , quotes 6 and 7).
How ev er, alongside this e xcitement , participants expressed c onc er ns about the exper imen tal na ture of r egenerativ e implants, particularly when it inv olv es implanting them in a child.Patients and parents worry about the potential unknown side effects and approach it with a certain level of caution, as they would not w an t themselves or their children to be treated as guinea pigs ( Table 3 , quote 8).Three factors w er e mentioned that c ould reduc e their c onc erns.First, the need for t esting was discussed as an important element by patients and parents of children with cleft pala te.Participan ts express their desire to know about previous testing, the out c omes and pot ential c onsequenc es .Older patients , in particular, do not w an t to take unnecessary risks and emphasize the importance of gathering more experience with r egenerativ e implants.Second , trust in the medical professionals plays a significant role in the willingness t o embrac e this novel t echnology.This was mainly discussed by the parents in the Spanish focus group, who appeared very trusting of their clinician's opinion on r egenerativ e implants and showed less hesitancy toward these implants ( Table 3 , quote 9).They argued that if the clinician said it was trustworthy and that this treatment added value, they would let their children undergo this (experimen tal) trea tmen t.Thir d , giv en the novelty of r egenerativ e implants, both professional experts and pa tien ts emphasized the need for long-term ev alua tion of implant performance and outcomes, both positive and negativ e. Ther efor e, pr oper ev alua tion mechanisms are essential to assess the long-term effectiveness of these trea tmen ts accura tely.Another reason for proper ev alua tion mechanisms pointed out by professional experts w as tha t pa tien ts often do not c ommunicat e their c onc erns or dissatisfaction with their trea tmen t to their surgeon directly but on pa tien t forums only.

Personalization
The idea of personalizing r egenerativ e implants led to discussion in all focus groups.Especially in the professional expert focus gr oup ther e was discussion about wha t personaliza tion is and how implan ts should be personalized .A pr ofessional expert raised the question of how we should define personalization and which parameter should be personalized .Numer ous parameters w er e explored during these discussions, including the external and internal structure of the implant, pore size, surface characteristics , mechanical properties , biolog ical fact ors and even the pa tien t's lifestyle .Furthermore , professional experts underscored gender as a crucial factor in personalizing r egenerativ e implants.
Personaliza tion w as rec og nized as an adv an tage and disadv an tage.On the one hand, personalization was mentioned as a benefit because it can be tailored to a particular individual with specific needs ( Table 3 , quote 10).This was also endorsed by pa tien ts and paren ts.A professional expert suggested that personalized implants c ould influenc e pa tien ts' a ttitudes.For example, upon P6: It has to do with wear and tear and with that other lady too, we have been living a bit longer.So yes, it is only logical that there will be defects.-Patient rec og nizing the trea tmen ts' personaliza tion, they may be more inclined t o c ooperat e with the trea tmen t and understand that part of the suc c ess of the trea tmen t is in their hands (and could for instance be affected by quitting smoking).
On the other hand, personalization was mentioned as a disadv an tage because it makes implants more complex and ther efor e driv es up the costs.This also r einfor ced the c onc erns that w er e expr essed r egar ding the ac c essibility of r egenerativ e implants.Both pr ofessional experts and pa tien ts questioned whether the implants would be ac c essible t o ev ery one or only to those who could afford them ( Table 3 , quote 11).Two factors w er e mentioned that could mitigate this contradiction.First, it was mentioned that a balance should be achiev ed betw een the wishes of all stakeholders, because not all needs can be met within one implant design ( Table 3 , quote 12).Second , a pr ofessional expert suggested that ther e is a need to look at the long-t erm c ost-effectiveness of r egenerativ e implants.This professional expert explained that the implants will be expensive in the beginning but when it reduces morbidities and surgeries in the longterm, it will be more cost-effective.

Metaphors & language
Participants in all focus groups used r eductiv e language, metaphors or terminology when discussing personalized r egenerativ e implants.On multiple occasions, respondents made comparisons between the body and a car, highlighting similarities in terms of maint enanc e and repair ( Table 3 , quote 13).This metaphorical language served t o c onc eptualize and discuss medical interventions within a familiar framework.For example, an older pa tien t used a body-as-car metaphor to explain the aging process of her body ( Table 3 , quote 14).Similarly, pa tien ts used phrases such as 'cutting open' or 'opening up' when refer r ing to surger ies and fixing bodily issues ( Table 3 , quotes 15 and 16).
In these instances, participants seemed to reduce their bodies to entities requiring repair.This way of speaking about their bodies was r emarkable giv en that both pa tien ts and paren ts also stressed tha t effective trea tmen t is about much more than merely fixing one's body -it should lead to a fulfilling life aligned with their personal goals.The data thus seem to reflect an ambivalence: on the one hand, they discuss their bodies and the trea tmen ts in reductionist terms, viewing them as entities requiring repair, while on the other hand, they emphasize the need for trea tmen ts tha t respect their broader wishes and needs and align with their individual life goals.

Age & ageing
Age was frequently mentioned during the focus groups with professional experts and pa tien ts, with these different stakeholders bringing up contrasting views.On the one hand, age was mentioned as a necessary selection cr iter ion for r egenerativ e implants.In the expert focus gr oup, ther e was discussion about age-related regenerative capacity and who would (not) be eligible for such implants.Children were identified as an eligible user group for regenera tive implan ts due to their need for tailored and individualiz ed solutions.Moreo ver, it was noted that elderly patients with osteoarthritis, who predominantly suffer from joint degeneration, do not experienc e sig nificant g r owth or r egener ation, suggesting that these patients would benefit less from personalized r egenerativ e implants.In contrast, another expert suggested that older individuals receiving personalized implants may experience impr ov ed healing and fewer c omplications c ompared with traditional metal implants.Within the expert focus gr oup, childr en w er e identified as an eligible user group for regenera tive implan ts due to their need for tailored and individualized solutions.
On the other hand, pa tien ts had differen t opinions about using age as a selection cr iter ion for r egenerativ e implan t trea tmen t.Some participan ts struggled with fears of age discrimination because of their older age ( Table 3 , quote 17).At the same time, they also stressed the importance of accepting their natural aging process ( Table 3 , quotes 17 and 18).

Discussion
As far as we know, this is the first study exploring the perspectives of pa tien ts, paren ts and professional experts on r egenerativ e personalized implants.Although these stakeholders generally welcomed the introduction of such implan ts in to regenera tive medicine in terven tions for multiple several musculoskeletal applications, they addressed the importance of pa tien t-cen ter ed r esear ch and care (theme 1) and also expressed an ambiv alen t a ttitude tow ard these implan ts (theme 2).
This first exploratory study gives an impression of the relev an t themes to set the further r esear ch agenda for the r egenerativ e medicine and tissue engineering field.In what follows, the implications and relevance of this qualitative study are considered, the findings are linked to the broader literature and underexplored topics are highlighted.

Insights for research & care for the broader healthca re doma in
Our study results reveal insights that are relev an t for the br oader healthcar e domain.This is mainly r eflected in the first theme on pa tien t-cen ter ed car e and r esear ch and related subthemes of support, institutional and interdisciplinary collaboration, living one's life and metaphors and language.

Beyond technical & clinical aspects of personalized regenerative implants
T he first o v erar ching theme pa tien t-cen ter ed r esear ch and car e underscor es the necessity for healthcar e pr ofessionals to look beyond the mere technical and clinical aspects of personalized r egenerativ e implant tr eatment.
It is crucial for them to recognize the significance of addr essing the br oader impact of the medical interv ention on pa tien ts' lives.In the wider litera ture on pa tien tc ent er ed r esear ch and car e, this is often r eferr ed to as a holistic approach -a t endency t o acknowledge the person's entire life [ 23 ].Coordinated care is also cited as a crucial element in this appr oach, inv olving coordination across the health sy st em and interprofessional collaboration [ 23 ], which aligns with elements discussed under the subtheme of institutional and interdisciplinary c ollaboration.In the lit erature on implants, particularly on knee/join t implan t trea tmen ts, the importance of a holistic approach is also emphasized [ 17 ].Moore et al. [ 17 ] further suggest that if a patient enc ount ers challenges with incorporating an implant, clinicians should engage in sensitive communication and actively list en t o those experiencing such difficulties.Thr ough support, activ e listening, r ecognition and alida tion of pa tien t c onc erns, as well as the int eg ration of their experienc es int o the decisionmaking pr ocess, healthcar e pr oviders can deliv er more pa tien t-cen ter ed and effectiv e car e.This will help to bridge the gap between the clinical perspective and the pa tien t's lived experience and might lead to bett er out c omes and increased pa tien t sa tisfaction with trea tmen ts with personalized regenera tive implants.
The key to a pa tien t-cen ter ed appr oach is to addr ess the purpose of the trea tmen t.The da ta of this focus group underline that when healthcare providers and their pa tien ts are not aligned in their trea tmen t goals, this can result in adverse trea tmen t out c omes, misc ommunication and dissatisfaction with the tr eatment.Ther efor e, establishing a shared understanding of trea tmen t objectives is essential for ensuring a suc c essful and pa tien tc ent er ed tr eatment.
How ev er, such shar ed understanding of the main trea tmen t objectives, whether involving regular implants or personalized r egenerativ e implants, is not y et w ellestablished.In this study, pa tien ts and paren ts emphasized the sig nificanc e of both regular and personalized r egenerativ e implants in enabling recipients to lead fulfilling lives, indicating this as the main trea tmen t objective.At the same time, pa tien ts perceived tha t their clinicians w er e pr imar ily focused on fixing the defect.Additionally, explicit discussions about the trea tmen t objective w er e not observ ed among the pr ofessional experts, who mainly c onc en tra ted on clinical and technical aspects of personalized r egenerativ e implan ts.Other qualita tive studies with experts did touch upon the primary goals of trea tmen t with regenera tive medicine applica tions.For example, in the study of Niemansburg et al. [ 14 ] experts observed that the field should engage in a thoughtful deliberation r egar ding the goal of r egenerativ e medicine -whether it should pr imar ily focus on tissue regeneration or pr ior itiz e the impro vement of patients' symptoms and ov erall w ell-being.

The impairment discourse versus the partic ipa tory discourse
These two perspectives on the goals of regenerative medicine applications such as personalized r egenerativ e implants are intricately connected to the discourses surrounding illness and trea tmen ts.Bunzli et al. [ 24 ] r eflect on tw o c ommon disc ourses in discussions on knee osteoarthritis: the impairment discourse and the participat ory disc ourse.
The impairment discourse centers on the limitations of individuals due to their condition, treating the body as a machine [ 24 ].Rooted in mind-body dualism, it per ceiv es the body as a physical object requiring specialized 'mechanics' , like orthopedists, to fix breakdowns, with pain alleviated only thr ough r epairing damaged body parts [ 24 ].In contrast, the participat ory disc ourse emphasizes individuals' capabilities despite their limitations [ 24 ].Clinicians aim to empower pa tien ts, v aluing an active body and considering the social c ont ext's role in shaping illness experiences rather than solely focusing on fixing defects (such as the knee joint) [ 24 ].This approach acknowledges that while anatomical changes may be beyond an individual's control, individuals can influence modifiable social fac tors impac ting their health.It advocates for informed choices promoting an active lif estyle and health y ag ing, rec og nizing that some may lack the ability, skills, c onfidenc e or r esour ces for such decisions [ 24 ].
The impairment discourse is reflected in the data from this study at tw o lev els.First, pa tien ts frequen tly mentioned that healthcare professionals tended to overlook their broader desires and needs, focusing pr imar ily on rectifying ph ysical def ects.The f ocus of these healthcare professionals is in line with the impairment discourse.The impairment discourse is also recognizable in the fields of medicine and r egenerativ e medicine mor e generally, where it is common to see the body as an object that can be r epair ed , r estor ed or r eplaced [ 25 , 26 ].How ev er, the body is also a subject and the c ent er of human experience, as has been explored extensively by philosophers, particularly in the phenomenological tradition [ 27 , 28 ].This entails a stronger focus on the dayt o-day experienc es of pa tien ts and their rela tionship with their bodies .C orrespondingly, an important next step for futur e r esear ch is empirically exploring what it is like to live with personalized regenerative implants.Thus far, this has been difficult due to the limited number of individuals currently living with such implants.Ther efor e, a theor etical exploration of available empirical phenomenological lit erature on experienc es with existing implan ts migh t serve as a valuable first step in this research endeavor.
Second, the impairment discourse is reflected in the use of r eductiv e language, metaphors and terminology within the focus gr oups.Pr ofessional experts fr equently employ such language and focus on technical and clinical aspects when discussing pa tien ts' bodies and pa tien ts and parents adopt similar language when addressing their (or their child's) illness and trea tmen ts.These linguistic expressions reduce the body to an object and aligns with the idea that the body can be mechanically r epair ed or alter ed .W hile these phr ases may be pr actical in conveying the nature of medical procedures, they may also c ontribut e t o an objectification of the body by reducing it to a mere entity in need of physical modifications and may thereby draw a tten tion aw ay from the broader wishes and needs of pa tien ts.
At the same time, the results of our focus groups show that there is an implicit desire among pa tien ts and parents to shift toward a participatory discourse.This shift is reflected in the data in multiple ways.For instance, paren ts articula ted a desire for less disruption in their childr en's liv es.Pa tien ts oft en c ent er their discussions around what they can achieve after receiving a personalized r egenerativ e implant, like swimming or walking their dog, reflecting the participatory discourse's focus on capabilities before and after trea tmen t.Additionally, they expr ess a desir e for clinicians to understand what it means to live with a particular disease or defect.Within this discourse, a healthy joint is one that facilitates an active life throughout one's lifespan and it does not necessarily imply a c omplet e cure.Thus, it becomes important to gain deeper insight into treatment and r esear ch objectiv es that all stakeholders have in mind r egar ding personalized r egenerativ e implants.
Facilitating this shift in discourse is important as adhering to the impairment discourse can have negative implications [ 24 , 29 ].First, this discourse has the potential t o disc ourage individuals fr om activ ely engaging in their own care, fostering a greater dependence on clinicians for body r epair [ 24 ].Second , clinicians who pr edominantly use an impairment approach may overlook the need t o enc our age active management str at eg ies or offer psychological support for the failing body machinery of individuals [ 29 ].Thus, in medicine in general and r egenerativ e medicine in particular, we should facilitate such shift in the way we talk and approach the individual, their body and illness.

Insights for personalized regenerative implants & regenerative medicine
Our study also r ev eals insigh ts tha t ar e specifically r elev an t for regenera tive implan ts and regenera tive medicine applications more broadly.This is particularly reflected in the second ov erar ching theme of ambiv alen t a ttitudes to ward personaliz ed r egenerativ e implan ts.This ambiv alence echoes similar sen timen ts expressed by stakeholders in the literature concerning new (bio)technology in medical healthcare.For instance, a study exploring clinicians' perspectives on artificial int elligenc e as a medical decision aid r ev ealed a clear ambivalence in the data [ 29 ].
Clinicians per ceiv ed artificial int elligenc e as a job threat but also acknowledged the potential benefits for patient care [ 30 ].
There is no consensus on the consequences of ambivalenc e in t echnolog ical change proc esses [ 30 , 31 ].Some argue tha t ambiv alence should be either avoided or r esolv ed and that suc c essfully addressing ambivalenc e is a crucial step in adapting to technological change [ 30 ].
It is argued that it can lead to confirmation bias and var ious for ms of resistanc e t o change, including defensiv e r eactions, noncooperativ e behavior or activ e r esistance [ 30 , 31 ].How ev er, this perspectiv e is ev olving, with scholars now also c onsidering ambivalenc e as a potential facilitator of positive outcomes [ 30 ].For instance, ambivalence may foster openness to change, adaptability and positive attitudes toward minority groups [ 30 , 31 ].Some of the ambiv alen t a ttitudes iden tified in this study w er e linked t o charact eristics of the implant itself, particularly personaliza tion.Personaliza tion w as viewed as a potential contributor to impr ov ed car e tailor ed to individual needs, alongside c onc erns about associat ed c ost increases.A similar ambivalenc e was found in the literatur e betw een the per ceiv ed benefits of personalized medicine (impr ov ed healthcar e and health benefits) and its risks (increased health insurance costs and uncertainty about coverage of personalized medicine) [ 32 ].One poten tial explana tion for this ambiv alenc e may st em from the lack of clarity in the meaning of personalization.In this study, as well as in the literature [ 32 ], there appeared to be v arying in terpreta tions of wha t personaliza tion en tails.Conducting follow-up r esear ch to explor e whether a clearer understanding of personalization could mitigate ambiv alen t a ttitudes tow ard aspects of personalized r egenerativ e implants would be a valuable next step for investigation.
To date, we have not enc ount ered similar ambivalence within the field of r egenerativ e medicine.The exploration of how various stakeholders discuss the possibilities and challenges of personalized r egenerativ e implants in our study provides v aluable insigh ts for the ongoing development and use of these implants.These insights are crucial for enhancing communication with patients and parents, guiding decisions in c onsent proc edures and determining whether to opt for a personalized regenera tive implan t .This encompasses for e xample aspects such as the growth and fixation of the implant and the diverse experiences that different stakeholders have with this characteristic.
While our study has identified ambivalence in discussions surrounding personalized regenerative implants, the reasons for this phenomenon and its specific effects in this c ont ext remain unclear.Understanding why and when ambivalence arises are critical r esear ch endeav ors to fully develop the potential of personalized regenerative implants.During the development and use of personalized r egenerativ e implants, r esear chers should addr ess ambivalence among professional experts, patients and parents, keeping in mind that ambivalence is not inheren tly nega tive.

Limitations
The results of this study should be int erpret ed within the c ont e xt of several limitations.First , the scope of the study w as rela tively broad.Given that this was the first qualitative study on the perspectives of pa tien ts, paren ts and professional experts regarding personalized regenera tive implan ts, it allow ed r espondents to raise issues they deemed relev an t.Further r esear ch is needed to delv e more deeply into these topics such as the embodied experience of recipients of personalized r egenerativ e implan ts.Second, any qualita tive study is influenced by the positionality of the moderators and r esear chers; a differen t modera tor and r esear cher might hav e focused on different aspects of the r espondents' answ ers and categorized the codes and themes differ ently.Thir d , the focus groups were c onduct ed in various languages, including Dutch, Spanish and English, with transcripts subsequen tly transla ted in to English when necessary.During the translation pr ocess, ther e is a potential for information loss or misinterpretation of w or ds.Fourth, the focus groups included participants predominantly born, raised and living in Eur ope, r eflecting a mainly Eur opean perspectiv e. Conducting similar studies in different global regions may yield different views and opinions on personalized r egenerativ e implants.Finally, not all input provided by pa tien ts and parents of children with cleft palate is directly related to personalized r egenerativ e implants, as none of them or their children had such implants themselv es.Nev ertheless, the themes they addressed hold relevance for the current field of r egenerativ e medicine, offering valuable best practices and highlighting critical elements requiring attention or impr ov ement in the development and use of personalized r egenerativ e implants.

Conclusion
It is expected that the use of personalized r egenerativ e implants in healthcare will increase in the near future.While these implants have a range of potential benefits, they also raise important challenges.This study helps to understand the perspectives of professional experts, pa tien ts and parents of patients on the ethical aspects of personalized r egenerativ e implants.The obtained r esults provide a valuable first step for emphasizing the need for pa tien t-cen ter ed car e and r esear ch within r egenerativ e medicine and exploring ambiv alen t a ttitudes tow ard personalized r egenerativ e implants.Further evaluation of these insights and other ethically relev an t aspects of personalized r egenerativ e implants should take place in co-creation with diverse stakeholders in parallel to the t echnolog ical development of these implants.In this way, these considerations can inform the development and implemen ta tion of personalized r egenerativ e implants and facilitate their ethical and responsible development.

Background
• It is largely unknown how patients, parents and professional experts think about personalized r egenerativ e implants.• Learning more about their perspectives is relevant because it can assist in aligning the design and implementation of these implants with the needs and desires of stakeholders such as patients, engineers and clinicians.

Results
• The first ov erar ching theme that emerged from the focus groups was the importance of patien t -cen ter ed r esear ch and car e. Thr ee subthemes w er e iden tified: (a) support and e xpectation management, (b) institutional and interdisciplinary c ollabora tion, (c) the implant's contribution to living one's life.• A second theme explored in the focus groups c onc erned participan ts e xpressing ambivalen t attitudes t o ward the characteristics of personalized r egenerativ e implants, such as their r egenerativ e capacity, the novelty of this technology and the possibility for personalization.Discussion • The first ov erar ching theme patien t -cen ter ed r esear ch and car e underscores the necessity for healthcare professionals to look beyond the mere technical and clinical aspects of personalized r egenerativ e implant treatment.• In medicine in general and r egenerativ e medicine in particular, we should facilitate a shift toward participatory discourse and change the way we talk and approach the individual, their body and illness.• Some of the ambivalent attitudes identified in this study w er e linked to characteristics of the implant itself, particularly personaliza tion.Personaliza tion was viewed as a potential contribut or t o impro ved care tailored to individual needs, alongside c onc erns about associa ted c ost increases.• During the development and use of personalized regenerative implants, r esear chers should addr ess ambivalence among professional experts, patients and parents, keeping in mind that ambivalence is not inherently negative.

Conclusion
• The obtained results provide a valuable first step for emphasizing the need for patien t -cen ter ed car e and r esear ch within r egenerativ e medicine and exploring ambivalent attitudes t o ward personalized r egenerativ e implants.• Further evaluation of these insights and other ethically relevant aspects of personalized r egenerativ e implants should take place in c o-crea tion with diverse stakeholders in parallel to the technological development of these implants.

Table 1 .
Respondent groups.University Hospital and Hospital Infantil Universitario Niño Jesús).Professional experts were recruited via the European INKplant consortium and the Dutch Materials Dr iven R egeneration consortium.B oth consortiums wor k on r egenerativ e implants for tissue engineering.
Because everyone looks at it from their own perspective, they see their value.But it's, yeah, I, I see that for myself.I try to think from the patient and maybe from the orthopedic surgeons' point of view.But I'm not a patient and I'm not an orthopedic surgeon.So, I just try to think myself into that position.That one should really collaborate on a deep level with the people that actually have this expertise.Whereas we still often do our own work from our perspective and publish it this way.-Professional expert ) after many internal issues in the hospital, they decided to give me a new knee implant 8 years ago (…).It went well.And I must say that I didn't experience any problems afterward.I can walk again, however, I can't sit on my knee, but the doctor says: why do you need to be able to sit on one knee?I say, 'Well not to pray, doctor, you can do that in all kinds of positions, but just to g r ab something for instance' .But, like I said, that doesn't work.And I've been alone for a very long time, but you find solutions for everything.-Patient 12 P7: And now a year ago, I received a reverse shoulder because I had two torn tendons.(…) And I have to say, if I had known befor ehand , I w ouldn't hav e done it .It limits me a lot , I can't move m y arm an y further than this .I had to remodel m y entire house t o be able t o reach everything (…) and different clothing and so on.Because you can no longer do things yourself, like putting on something with a zipper.Anyway, the doctor says: then you would have kept the pain.But I say: now I have a different kind of pain, if I lift it higher than I should, it Because y ou feel like y ou'r e always informed about what's being discussed.-Belgianparent 8 DP6:But what I still find very particular is that, r egar ding cleft palates, there are still so many hospitals that all work with different approaches.(…) And I wonder whether [a regenerative] implant can soon be implemented in all hospitals.And the same goes for the age limit of the operation.In our [name hospital] we simply went 100 percent for closing the soft and hard palate at the same time to avoid further surgery.(…) for me the question arises (…) do hospitals even agree with each other on how they're going to perform cleft palate sur geries, bef or e w e start using a [r egenerativ e] implant?-Dutch par ent 9 EP3: I think, we, as scientists, we tend to stay too close to our, to what we know.-Professional expert 10 EP7: It's good to (…) have the other stakeholders have a look and give their estimation on the value, as well.hurts .An yway, I try to adapt and live with it , but this is not , this doesn't make it easy, the r ev erse shoulder.-Patient 13 DP4: Yes, I can imagine that it can be an impr ov ement on a psychological level if it can be limited to one or two surgeries or at least as few as possible.Because it can be traumatic, the fact that it all happens in this area.It concerns eating and well how [SP2] just described it, how challenging and intense that can be.I also experienced that when she was very little, unfortunately.Refusing to ea t .Ea ting, is of c ourse, a form of control that you can have when you have no control because surgeries have to take place.So, fewer traumas, fewer psychological c onc erns, c ould be an advantage and a c onsequenc e. -Dut ch parent 14 DP2: For me, driving back and forth every time to [city] is an issue.There have been periods, especially leading up to the last surgery, when we had to go to [city] weekly or bi-weekly.Each time he had to miss a day of school.That is, well, he is now behind in reading and writing, for example.He is catching up, but those things could be avoided if the last surgery is dismissed.So I think that's really important to take into ac c ount .-Belgian parent

Table 3 .
Illustrative quotes about ambivalent relationship with regenerative implants.She had to go through two operations because [during] the first one (…) there was really nothing to take hold of, right?Because it was such a huge fissure that maybe one of these solutions that goes along with the growth, it closes the fissure and makes everything more natural, in a more natural way, it could have been, it would have been a super good solution for [name child].-Spanish parent 2 DP4: And someone also said it and I thought about it too, how long, how far does it continue to grow?Won't it suddenly at some point, well I don't have any knowledge of it, but where does it somehow stop growing, or something?-Dutch parent 3 DP5: And yes, the fact that that tissue becomes one, so to speak, it is broken down and it [re]generates, I find that myself also a bit of a strange idea or something.It's something that you really have to get used to, that it is, in a way, actually doing something in the child's body, so to speak.-Dutch parent 4 EP5: (…) Second , as y ou all kno w and point ed out, it's not the same cartilage.So, [y ou] might as w ell tr ansplant something else.W hich is you know, synthetic.There are metal options.So, you can actually implant a little button in the hole.But that has not worked well.Because the fixation is really bad.So, the bone behind it dissolves.And so, the metal then, sort of, gets loose in the joint.Which doesn't, doesn't w ork v ery w ell .And then, y ou hav e applications in multiple joints.Equally, if y ou can r ecr eat e a t endon, w e hav e a massive problem in the rotator cuff in the shoulder.So, I think the potential [of personalized r egenerativ e implants] is, is definitely there.(…) -Professional expert 5 P3: Well, I think the regenerative aspect is perhaps more of a disadvantage, that it gets absorbed by your body.You see, if you just have an implant that's fixed, it won't wander through your body.If it gets absorbed, those cells have to go somewhere.It is something that is not in your body.Are there any studies on what will happen with this?Could it, for example, clump together in, I don't know, your lymph nodes, for example?That's a possibility.Could it trigger a reaction?Could it encapsulate?These are all questions that I think are very important to have thor oughly inv estigated .-Patient think it looks really awesome and I am, well, of course I find already that there, I think that new techniques are cool anyway, just like putting a pig's heart into humans, so I'm already enthusiastic about it.-Dutch parent 7 P5: That to me, sounds like music to my ears, because 3D and custom made in a mold, whether or not with an MRI, I don't know exactly how it all comes together, but that sounds fantastic.-Patient 8 DP5: Personally I think, you do insert something, which I personally would find a bit scary, regarding the e xperimen tal nature of it.So something tha t , w ell , that is not y et, with which ther e is no experience y et , the fact tha t you do tha t with y our child , w ell , to put it strangely, your child becomes a bit of a guinea pig, so to speak.Patient 16 P5: I can imagine that with a 3D-printed, well yes, you want new cartilage to grow, but the big problem is that you have to insert it somewhere.And for tha t , you often have to open up the knee or the shoulder or the hip.And if there were something that could put it in the right place, say, by means of encapsulation, then you wouldn't need the recovery from opening that knee, shoulder or hip anymore.That would be really great for me because, well, the recovery takes so much time: the skin is cut open, but there are also several layers underneath, you have to get to the right place, it is exposed and ther efor e susceptible to bacteria and such.-Patient But everything is subject to age.And I don't want people to discriminate against me because I am almost 55 years old: which means it is no longer possible.Anyway, I will also have to deal with the fact that as I get older, my body may no longer r ecov er as quickly and as good/effectively.And it is about finding balance and one body is not the same as the other, one is stronger than the other and some still r ecov er at an old age.-Patient 18 -Dutch parent 9 SP5: For, for him, so, w ell , no, we would not mind because we trust [name doctor] blindly, for us she is, she is a magician, she has directly performed magic with, with our son, eh and and if she tells us look, these are the first ones but we are sure tha t , tha t it will go w ell , it has good results that have already been shown, we would do it of course.-Spanish parent Personalization 10 EP4: Since all kind of palatal defects are completely different in shape.So, when we talk about personalized, I think, it's really helpful.So that the implant fits perfectly into the defect size.It can be bilateral or unilateral.Or complete defect or partial defect.Yeah.So, this would be really helpful when it completely fits.-Professional expert 11 SP7: I think it is important and then the issue that I pointed out and here is the issue of equity, that is, this is something that, it will be funded or not funded, right?Because ethically it is also somewhat interesting and, well, if only those who can pay for it can ac c ess it or not, well, it should be taken into ac c ount and that's all.-Spanish parent 12 EP5: The Dutch are very keen cyclists.So are Belgians.There is a saying in road cycling: "Cheap, light and strong.Pick two".So, you need to, you can only have two out of three.So, we can't be cheap, complex and perfect.So, if it can't be cheap.At least, it has to be better than what's biolog ically av ailable.And I think, this applies to this perfectly.-Professional expert Metaphors and language 13 EP6: Yeah.I think tha t , of course, some of this reminds me of the repair of a car.If you're going to be of this and it has to come out working.And I think, maybe we would have to sort of change the way we treat these things.-Professional expert 14 P6: Take an old car, you can install a new part and the others start wearing out faster too.And that's how I see our bodies too.-Patient 15 P2: My knee has been opened up four-times in 2.5 years.(…) At first, you think, well, just cut it open and fix it.-